C++ Creator Wants To Solve 35-Year-Old Generic Programming Issues With Concepts (cio.com)

C++ creator Bjarne Stroustrup is arguing that we can improve code by grounding generic programming in concepts -- what's required by a template's arguments. An anonymous reader quotes Paul Krill's report on a new paper by Stroustrup: In concepts, Stroustrup sees the solution to the interface specification problem that has long dogged C++, the language he founded more than 35 years ago. "The way we write generic code today is simply too different from the way we write other code," Stroustrup says... Currently an ISO technical specification, concepts provide well-specified interfaces to templates without runtime overhead. Concepts, Stroustrup writes, are intended to complete C++'s support for generic programming as initially envisioned. "The purpose of concepts is to fundamentally simplify and improve design. This leads to fewer bugs and clearer -- often shorter -- code"...

Concepts, Stroustrup believes, will greatly ease engineers' ability to write efficient, reliable C++ code... The most obvious effect will be a massive improvement in the quality of error messages, but the most important long-term effect will be found in the flexibility and clarity of code, Stroustrup says. "In particular, having well-specified interfaces allows for simple, general and zero-overhead overloading of templates. That simplifies much generic code"
Concepts are already available in GNU C Compiler 6.2, and Stroustrup wants them to be included in C++ 20. "In my opinion, concepts should have been part of C++ 17, but the committee couldn't reach consensus on that."

Comments

Epicycles

[helixcode123]

The vagaries and complexities of C++ as it progresses in it's specification is reminiscent of efforts to get epicycles to explain motions of heavenly bodies. Geez, people are snide about Perl syntax. Now we have &ref, &&global_ref, [](args){my_lambda_code();}, copy constructors, move constructors, 'override' to fix virtual function breakage. This is just a mess of a language.

Re:Just what we needed

[Dutch Gun]

Well, part of being a professional programmer, at least IMO, is not going batshit-insane with fancy language features when they're not needed. C++ is a language in which you can write some really, really horrible code if you're determined to do so. And I don't think I've ever heard anyone describe it as a language that's easy to master. But for highly experienced C++ programmers like myself, it's an incredibly powerful language, and that's what's important, at least when I use it professionally.

It's pretty easy to list off a litany of problems with C++. It's bloated, it's ugly, it's hard to learn, full of strange idioms and tricky rules. But it has three characteristics that make it indespensible for certain industries and applications:

* It's ubiquitous. Nearly every platform has a C++ compiler, and there's a lot of sample C or C++ code available to use. It also makes hiring and training easier.
* It's efficient. You don't pay for features you don't use, and it compiles down to fast, efficient, native code.
* It's got reasonably good abstraction features that don't require paying a heavy price for that safety, enabling large, complex programs to be written more easily.

There are a lot of great new languages coming out, but nearly all of those fail on the first point. Unfortunately, that's a deal breaker for many projects.